The present invention relates to a method for optically detecting gas bubbles in the cooling liquid of an internal combustion engine, where light is radiated into the coolant via at least one emitter and the scattered light caused by the presence of the gas bubbles, or rather, the change in intensity of light radiation emitted into the coolant, is measured by a sensor, and to a device for implementing this method.
The size, number and velocity of gas bubbles in the coolant of an internal combustion engine have an essential influence on the performance of the cooling system.